Today, lost and found operations are run at a fixed place within a facility where things are lost and found. Few examples include a school campus, a library, a recreation park, and an office facility. Additional lost and found operations are also run by public security offices such as police stations, etc.
There are popular web forums too where people post the found items. A person who lost a particular object may contact the finder through email, and/or a phone number, if listed.
There are also lost & found technologies implemented based on what could be termed as preventive technologies. An object is tagged prior to its transport (e.g., airline baggage) so that it is easier to locate, if lost during the move.